Weather permitting, a replica of the "Flyer" will stage a re-enactment of the brothers' feat at Kitty Hawk beach in North Carolina at 10:35amon Wednesday.

President George W. Bush is expected to use the occasion to make a keynote speech on US space ambitions.

The original flight by Orville Wright on December 17, 1903 lasted only 12 seconds. The brothers estimated that he reached an altitude of 36 metersfeet).

The re-enactment will cap a series of celebrations of the centenary, including an exhibit of the Flyer itself, and the launch of a new aviation museum near Washington.

Actor John Travolta, himself a pilot, will be master of ceremonies in North Carolina. Bush, whose presence has not yet been officially announced, was also a pilot in the Texas National Guard.

Reports have suggested the president could announce a new space flight to the moon, although the White House has said this is "speculation" and "premature."

In a huge tent on the beach, the public will have access to a simulator of the Flyer flight, be able to examine a piece of lunar rock, speak to NASA astronauts or take a close-up of a space shuttle engine.

The centenary celebration, launched a year ago, has met with huge success, with 10 million visitors having filed through Washington's Air and Space Museum. "People wanted to see the Flyer in 2003," said museum director Jack Dailey.

The museum has dedicated a special exhibit to Wilbur and Orville Wright and their ground-breaking flight.

The biplane was on display for the first time on the ground -- as opposed to suspended in the air -- to give a more realistic look at the fragile muslin-covered pine structure.

The stopwatch used in the first flight is also on display, as is Orville's mandolin and one of the bicycles the brothers made.

"This exibition not only celebrates the Wrights' remarkable technical triumph, but also the spirit of unyielding curiosity that made it possible," Dailey said.

Also on the centenary, a second aviation museum has been opened at Chantilly, near Washington's Dulles International Airport. The site allows the Smithsonian Institution to show up to 80 percent of its aeronautical collection.

Built like an aircraft hangar, the museum exhibits a number of its planes suspended like model aircraft in an array of spectacular flight maneuvers.

The museum -- "perhaps the largest room in the world" -- according to Smithsonian director Lawrence Small, has the first space shuttle, the B-29 Enola Gay that dropped the atomic bomb over Hiroshima, and one of the now retired supersonic Concordes.

Temporary exhibitions have proliferated in recent months. Three weeks of events in Dayton, Ohio commemorated the brothers' departure from their birthplace to the North Carolina sand dunes in their bid to get their plane off the ground. The mission was accomplished.

SPACE.WIRE